Gear-cutting machine.



C. E. DERR.

GEAR CUTTING MACHINE.

APPLICATION FILED MAY 28| 1914- Patented' Feb. 1, '1916.

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. C'. E. DERR.

GEAR CUTTING MACHINE.

APPLICATION HLED MAY 28, 1914.

Patented Feb.. 1, uns.r

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GEARr cumNe MACHINE. y I APPLICATION FILED MAY 28, I9I4.'

Patented Feb. l, 1916.

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CHARLES E. DERR, 0F DETROIT, MICHIGAN, AssIGNoR To PACKARD MOTOR CAR COMPANY, oP DETROIT, MICHIGAN, A CORPORATION or MICHIGAN.

GEAR-CUTTING MACHINE.

Grig'inal application filed February 11, 1913, Seria-.1 No. 747,677. Divided and this application filed May 28, 1914. Serial No. 841,608.

To all 'whom t may concern Be it known that I, CHARLES E. DERR', a

citizen of the United States, and resident of Detroit, lVayne county, State of Michigan, have invented certain new and useful Improvements in Gear-Cutting Machines, of which Athe following `is a specification.

This application is division of co-pending 'application Serial No. 747,677, filed- February 11,1913, and relates to gear cut'- ting machines, particularly tocertain improvements whereby bevel gears having curved or skewed teeth are adapted -to be cut on 'such machines. l One of the objects of the invention yis to provide a simple, rigid construction for efficiently operating the cutting tool.l I

Another1 object is to provide a construction which is 4not subject to excessive wear.

A further object is to provide a carriage having the toolcariying apron so pivoted in relation to the path of travelofthe tool that out interference with .the teeth which are being cut.

Another object is to provide improvedv means for lifting the tool carrying apron on the return stroke of the tool.v

Other objects and the features of novelty will be apparent from the following descrip-- tion, taken in connection' with the drawings, in which:

Figure 1 is a plan view of a portion of a gear cutting machine embodying my improvements; Fig. 2. is a sideelevationofl parts shown inF ig. 1; Fig.' 3 is a side elevation of the tool holder and aiportion 'of the I tool carriage; Fig. 4 is a front elevation of the tool holder and carriage; and Fig. 5 isa detail section of la part of the tool lifter mechanismas shown substantially on the line 5-5 of Fig. 1.

.In the embodiment of my invention shown,

it will be seenon reference to th'e'drawings,

that 10- indicates the frame of the machine on which is slidably mounted the ram 111 having secured thereto the head 12. 'The head 12 is provided witha suitable dovetail slot 13 in its front face in which 1s' arranged Vthe dovetail 14 of the -tool carriage 15. The

carriage 15'has pivoted thereto the tool supstantially at right angles to the direction of ymovementof the tool.

upon which this invention is an improvement, this machine is especially adapted-for Patented Feb. 1, 1916. y

in the case of'my prior application,l Serial No. 725,328, "iiledOctober 11, 41912,

cutting bevel gears having spiral or curved teeth and the curvature ofthe teeth is formed by combining with-the usual reciprocating `movement of the ramand tool carriage, a

transverse movement of the carriage.- The ram and the tool carriage may be reciproy cated in any suitable manner and for this purpose I have provided agearA-wheel 17 mounted on a shaft 18 and driven" from any suitable source of power.. The vwheell 1 7 carries an adjustably arrangedfcrank pin 19 which is connected with: a pin 20 on 'the ram 11 by means of connecting rod 21. The

location of the crank 'pin l19 relative to the axis of the shaft 18 is-adjustable for'the purpose of varying the stroke of the ram 11.

the latter may be lifted from the blank with- In orderA to move the tool carriage laterally a plate 22 may be secured to the frame 10 beneath the carriage and having a raised central portion 23 provided withthe circular edges 24 and 25, this raised portion thus constituting a pivot for alplate 26 which is' secured on the plate22 by me'ansof suitable bolts 27 passing through slots 28 in the plate 26. The plate 26 as thus arranged constitutes a form of turn table. In order to hold the plate 26 in any desired position, the plate 22 is provided with the lugs 29 through which pass the adjusting screws 30, these screws vengaging one v,of the edges of the plate .26 s'othat by turning these screws in ,opposite directions it is possible to swing the plate 26 on the raised portion 23 of the plate cam roller 32-carried by on the" tool carriage 15.

Itwill be obvious that-"as the -ram 11 is the 'pin or bolt 33 reciprocated the tool carriage will be moved,

laterally by the engagement of the'roller 32 withthe-edges of the camslot 3l. In order toprevent back 'lash'of the roller 32 in the slot 31 and/maintain the roller in yieldable I cured tothe tool carriage 15 and the bracket .22. The 'plate '26 is provided with a suit- -ably formedcam slot- 31m 'which moves the 37 is secured to the head l2 of the ram ll. The bolt or pin 35 is preferably secured in the bracket 37 so that as the ram reciproca the spring 34 will be alternately lcontracte i' and extended and will maintain the roller 32 in yieldable contact with the side 2S of the cam slot 3l.

The tool apron 16 has arranged on its front face the tool holder 39, this holder being held in position by means .of a clamping vPlate el, which is fulcrumed on the screw 40 and has its side forced into engagement with the tool holder, to secure the latter, by means of a screw -lf' The tool holder 39 may be adjusted vvertically by means of a 'screw 44 whicl is held in a bracket i5 on the apron 16. The tool holder is provided with a dovetail slot in its lower side which receives the wedge shaped tool e6, the cutting edge t7 of which is arranged at the.

forward end of the tool, 'lhe 'rearward end 48 of the tool C is beveled and has arranged in engagement'therewith awedge f4.9 which may be adjusted'vertically by means of a screw o() for the purpose of moving the tool forwardly. lThe tool may be 'clamped in any desired position by means of a set screw 5l. in order to yieldably retain the apron i6 in its operative position againstl the forward face of the tool carriage l5, lhave provided on the under side of the carriage a spring 52, this spring being connected with suitable arms 'andY 54 on the' apron and carriage, respectively.

ln the operationof themachine'the tool i6 .makes a cut in the blank A on the forward stro-ke and in order to lift the tool out of the space between the teeth, on the return or `rearward stroke, l provide on one Vside of the apron a pin or roller which is adapted to be engaged by a cam 56 on a shaft 57. The shaft 57 is mounted in a suitable bearing 58 at the side of the carriage '15 and yis connectedavith a shaft 59 by means of a telescopic shaft 60 a'nd'thel universal joints 6l and S2.' rlhe shaft 59 is mounted in bearings G3, (Se on the frame l0 'and carries-a bevel gear 65 which meshesv with a gear 6G. on the shaft G7, the latter shaft being mounted in bearings 68 and 69, and also carrying a gear 7,0. The gear 4 70 mcsheswith ageas7lfon shaft 72, this shaft being mounted in a bearing 73 and also carrying a `gear 74. nlfhe gear 7;@

meshes with a segmental gear 75 which is carried .by one arm 76 of a bell-crank Vpirotally'imounted at 77 on a suitable bracket The othenarm 79 of the bell-'crank c'arrieSa caml roller 80 arranged in a cam` "slo't 8l in the side of the gear 17, this cam ot being so formed as to rock the bell cra/nk on the pivot 77. l,

As will Abe readily understood 'the rocking'ofy thebell crank effects a rotation of the gear 74 and the cam 56, the arrange,

i raise the tool lt mately the end of the rearward stro eklig movement. roi-med that the apron i6 w swung on pivot ill sul'licientljv 'to the tool l5 out of the tooth space il blank The cani slot Sl is so forni@ l relation to the position of the crai at the end of the r rd stroke of the tool and maintain elevated position until it reaches y ne, when the tool will be permitted to fall to its operative or cutting position. lt will be observed that the shaft 57 is on the tool carria ge and the telescopic shaft GO and the universal joints Gl and 62 provide for the movement of this shaft relative to they finte(n shaft 59;

lt is believed that the operation of the t,

machine will be thoroughly understood from the foregoing description taken in connection with the drawings. lt will also be understood vthat various changes may be made in-the details of construction of the parts of the machine within the lscope of my .invention` as ldefined in the claims, and

therefore do not wish to be limited to i e exact details of construction shown and ie-- thus described my invention, claim and desire to secure by Letters w iat Paten r l. a gear cutting machine, the combination of a frame, a ram slidably mounted thereon7 a tool carriage movably mounted on said ram, and means comprising a telescopic operatingshaft connected to said carriage.

2. ln a gear cutting machine, the combination of'a frame, a ram slidably mounted thereon, a tool carriage slidably mounted on theram, a tool holding apron pivoted to the carriage, and means comprising a iiexible operating shaft connected to said carriage 'piyoted to the carriage, a rotatable cam on said carriage adapted to swing said apron on its -pivot, and means for rotating said earn.

ln a. gear cutting machine, `the conibinati'on of a frame,`a ram slidably mounted thereon, a tool carriage slidably mounted on the ram, a tool holding apron pvoted to the bmation of a frame, a ram slidably mounted thereon, a tool carriage slidably mounted on the ram, a tool holding apron pivoted to said carriage, a rotary cam for swlngmg said apron on its pivot,:anoperatingshaft mountedloi said frame, a flexible shaft connecting said operating shaft and saldv cam, means including a segmental gear for actuating said operating shaft, and cam means for rocking said segmental gear.

In testimony whereof I affix my signature y in presence of two Witnesses.

CHARLES E. DERR. Witnesses: v v

CLAIR J. COTE, -LE Roi P. WILLIAMS. 

